Answer:
Speed= 6 m/s
Velocity=-6 m/s or 6 m/s to the left
Explanation:
Speed is a scalar quantity and is always positive, while velocity is a vector; hence it must have a direction and a module (the speed).
In other words, the speed is the module of te velocity vector.
In this sense, average velocity and average speed are defined as:
(1)
Where is the object's variation in position and is the time
(2)
Where is the distance traveled and is the time of travel
Now, according to the given information, the person started at an initial position and finished at a final position .
This means the variation in position (assuming the person is moving along the X-axis or horizontally) is:
And
Then, the average velocity is:
(3)
(4) As we can see, the negative sign indicates the direction, which is to the left (or to the West if the person is traveling along a West-East highway, for example)
On the other hand, if we calculate the distance traveled by this person we have to take the difference between the two points:
As we know the time of travel is also , the average speed is:
(4)
(5)